Thread by @KelseyDav

Unsurprisingly #Iran's decision to slow production of 60% enriched uranium & its failure to follow through on expanding IAEA monitoring is grabbing headlines.
The 60% news is a positive step with limited value. No progress on monitoring is a real concern.
But there is more: 1/

-The May IAEA report said the agency completed its annual PIV (physical inventory verification). The Sept. 4 report said the results “found no indication of diversion of declared nuclear material.” This is particularly important because of the 83% particles detected at Fordow. 2/

-The Sept. 4 report noted that Iran reverted its production of 60% enriched uranium at Fordow to an earlier mode. So the IR-6 cascade with the modified subheaders (which can more easily switch between enrichment levels) is no longer producing 60% uranium. That’s positive. 3/

-Fordow remains equipped with 6 cascades of IR-1 centrifuges & 2 cascades of IR-6 centrifuges, despite plans announced in November 2022 to replaces the IR-1s & expand the overall number of cascades to 16 (a mix of IR-1s and IR-6s). Why no progress? 4/

It's not clear. But any expansion of IR-6s at Fordow would increase proliferation risk, given the location of the facility.

The only real change in installed cascades is the completion of a a long planned 5th (of 12) cascade of IR-4 centrifuges at Natanz. 5/

Are other centrifuges being produced but not installed? Has overall production slowed? If so is the reason technical or political? Hard to know given Iran’s refusal to allow the IAEA access to centrifuge production sites. And this will make future verification more difficult. 6/

-Of the 21 cascades of IR-2s installed at the Natanz Fuel Enrichment Facility, Iran still has not fed uranium into 12 of those cascades. Again, it's not clear why. But if Iran were to begin using these cascades it would significantly expand Iran's uranium enrichment capacity. 7/

-Since the May report, Iran transferred another 31kg of uranium enriched to 60% & 64.5kg of uranium enriched to 20% to the Fuel Plate Fabrication Plant at Esfahan. Now the total amount of 60% at the facility is 100kg & there is 454 kg of 20%. 8/

Will Iran convert the material to a less proliferation sensitive form? Not necessarily. But if Iran wanted to enrich the material further, say to weapons-grade, it would have to transfer it back to Natanz/Fordow. That takes time & the IAEA would notice. So that's good. 9/

-Iran has not produced any uranium metal over the past quarter. Another positive. Uranium metal is weaponization-related activity & the E3 in particular have warned Iran against further action in this area. 10/

-On Sept. 2 the IAEA was able to service surveillance equipment that it installed at the centrifuge production facility in Esfahan in May. Good, but the IAEA still does not have access to recordings (both since May or from Feb.2021-June 2022) & that's a real problem. 11/

-Iran also denied the IAEA's Aug. 28 request to install cameras at another centrifuge production site, despite agreeing in March to additional monitoring.

Iran is shooting itself in the foot by refusing to agree to additional IAEA monitoring & access. 12/

The longer these monitoring gaps persist, the more challenging it will be to establish credible new baselines & verify any limits on certain activities set in a future deal. That creates more challenges for future diplomacy & could undermine an agreement down the road. 13/

-Iran informed the IAEA in May 2023 that it intended to complete the Arak (Khondab) reactor based on a design agreed to under the JCPOA & begin commissioning in 2023. In the Sept. 4 report notes no real progress at the site & no updates. Not surprising but not a risk. 14/

-On the safeguards investigations the topline is that Iran is continuing to stonewall the IAEA. But the details of Iran’s engagement with the IAEA on this issue over the last quarter are interesting. 15/

-Regarding the material accountancy at the Uranium Conversion Facility, Iran appears to be arguing that the discrepancy was predictable due to the processes used for recovering uranium from waste. The IAEA is not buying that argument & the issue is still outstanding. 16/

-On Varamin & Turquzabad, the 2 undeclared facilities where the IAEA detected uranium still under investigation, Iran said in June it “exhausted all its efforts to discover the origin of such particles” & reiterated that no nuclear activities/storage took place at either site 17/

-In an Aug. 28 meeting Iran said it would provide the IAEA with more information regarding the containers transferred from Turquzabad & dismantled at another site. That would be positive, but I’ll believe it when the IAEA says it happens. 18/

Despite this lack of progress, censure at the Sept. IAEA BOG seems unlikely, particularly if the United States assesses that Iran is open to further deescalatory steps. 19/

Given the limited nonproliferation value of the 60% slowdown future diplomacy should focus on enhancing transparency & actions that would have a meaningful impact on reducing short-term nuclear risk & preserving space for diplomacy. 20/20